Bit gauge



G. H. mANMER.

BIT GAGE. APPLICATION FILED JAN.20. 1 922.

1,430,951, I Patented 0%;1922.

.Patented @et Si, i922.

entran a .gen1 pip BIT GUC-El Application led January 20, 1922. Serial ll'o. 539,556.`

To all w hom t 'may concern Be it known that I, Gnonen HORACE CRAN- MER, a citizen of the United States, residing at the city of Philadelphia, county of'Philadelphia, and State of Pennsylvania, have invented a certain new and useful lmproved Bit Gauge, of which the following is a specification. Y

This invention relates to a gauge for application to a bit, drill `or the like, to limit the depth of hole to be bored. l-leretofore devices of this character have not proven commercially satisfactory for the reason that the Working-end 4of the gauge-bar, or equivalent means employed, has aliv'ays been more or'less free to move when contacting with an article being drilled, the disadvantage of which is readily apparent. lt is one object of the present invention to overcome this disadvantageous feature and provide a construction in which the gaugebar may be fixed against movement in any direction, especially at its Working-end. that is, immediately adjacent the point of the bit or drill. Other and further objects relate to the provision of general details of construction and arrangement and combination of parts as will hereinafter more fully appear.

rlhe invention consists of the improvements hereinafter described and finally claimed.

The nature, characteristic features and scope of the invention will be more fully understood from the following description, taken in connection With the accompanying drawings forming part hereof, and in Which:

Fig. 1, is a view in elevation of a bracebit having applied thereto a gauge embodyingi features of the invention.

Tig. 2, is a view in elevation of the detached from the brace-bit and Fig. 3, is a top or plan view of Fig. 2.

For the purpose of illustrating my invention l have shown in the accompanying drawings one form thereof which is at present preferred by me, since the same has been found in practice to give satisfactory and reliable results, although it is to be understood that the various instrumentalities of which my invention consists can be variously arranged and organized and that my invention is not limited to the precise arrangement and organization of the instrumentalities as hereinshown and described.

gauge ln the drawings, 10 designates a gaugebar slotted adjacent its outer portion as at 11 and termii'iating at its opposite portion in a generally flared part 12. Means is present to clamp both of these portions of said gauge-bar to a boring tool which for illustrative purposes shown as being a brace-bit 13 although obviously a drill or similar tool may be employed. ln practice the outer portion of the gauge-bar 10 is disposed at an inclination to the brace-bit for a purpose about to be described.' lt is essential that the inner or Working-end of the gauge-bar 10 b e rigidly clamped to the brace-bit and in abutting` relation there- Jith lt is also essential that the outer or slotted end of the gauge-bar be positioned far enough away from the upper end of the brace-bit so that the jan7 which holds the same will not interfere with adjustments of said gauge-bar. lt is also essential that the outer or tiered end l2 of the gauge-bar project an appreciable distance to one side of the brace-bit to provide a positive stop. It is also essential that the gauge-bar may be adjusted vertically of the brace-bit. ln order to meet these special requirements best results have been obtained by providine: separate clamps, description of which will vnonr be given. Referring first to the inner clamp, 14 designates opposed, laterally extended angle pieces slotted as at 15 and movable endyvise through the grooved face 15 of the gauge-bar. A threaded stud 16 is fixed to the gauge-bar and projects through the slots of the angle pieces 141-, a nut 17 being present upon stud 16 for clampingI said angle pieces 14e around the brace-bit 13. ln this connection it is to be observed that the inner face of the gaugebar abuts against the brace-bit 13 and that the angle nieces 14e engage two sides of the brace-bit. rllhus clamped to place, the gauge-bar, when contacting -vvith an article as 18. upon completion of a boring period is held against siueyvise or tilting movement and is held against vertical movement by means of the clamp about to be described. 19 designates a block having an outer, beveled face which beveled face is provided With a tongue 2O for engaging Within slot 11 of gauge-bar 10. Block 19 is provided with a lined, threaded stud 21 which projects through tongue 20 and slot 11 so that the gauge-bar may be clamped to member 19 by` means of nut 22 to preclude vertical movement. Block 19 in turn is clamped to bit 13. It is sometimes de sirable to clamp block 19 to the shank of the brace-bit and at other times to the boring portion of thebrace-bit. lFor this reason a hinged element has been provided. Fixed to block 19 is a plate 23 having hinged relation 'with which is another plate 241. Both of these plates are provided with concaved portions 25 whereby a good purchase may be secured. around the curved surface of the brace-bit. Having pivotal relation with plate 28 is a threaded stem 26 provided with a nut 27 Which. stem is adapted to engage the slotted portion 28 oit plate 241 whereby, when the nut 27 is screwed to place blocl. 19 is securely clamped to the brace-bit.

l From the above description it will be noted that the gauge-bar may be securely clamped to the brace-bit at various points. For instance the inner end oi' the gauge bar may be positioned at any desired height upon the brace-bit 13 by means of the inner clamp and rigidly held in that position.

`'Ihe outer end of the gauge-bar may be clamped with respect to the brace-bit also at any desired height either to the shank of the brace-bit or to the boring portion thereof. By this arrangement and construction of parts pronounced rigidity of the gauge-bar may be secured which is advantageous in a device of this kind.

that I claim is:

In combination, a gauge-bar laterally grooved adjacent its Working-end, a pair of opposed angle-pieces movable through said groove and adapted to engage around a drill or bit, means for clamping said angle-pieces in place, a beveled member co operatively engaging-the opposite end of said gauge-bar, means for clamping the gauge-bar to the beveled portion of said member so that the outer end of said gaugebar is positioned tar enough away from the siank oit a drill or bit to permit vertical adjustment of said gauge-bar without regard lto the means for mounting the drill or bit shank and means carried by said member adapted to be clamped around a drill or bit.l

In testimony whereof, I have hereunto signed my nam e. GEORGE HORACE CRANMER. 

